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Short-term neuromuscular, morphological, and architectural responses to eccentric quasi-isometric muscle actions



Eccentric quasi-isometric (EQI) contractions have been proposed as a novel training method for safely exposing the musculotendinous system to a large mechanical load/impulse, with few repetitions. However, understanding of this contraction type is rudimentary. We aimed to compare the acute effects of a single session of isotonic EQIs with isokinetic eccentric (ECC) contractions.


Fifteen well-trained men performed a session of impulse-equated EQI and ECC knee extensions, with each limb randomly allocated to one contraction type. Immediately PRE, POST, 24/48/72 h, and 7 days post-exercise, regional soreness, quadriceps swelling, architecture, and echo intensity were evaluated. Peak concentric and isometric torque, rate of torque development (RTD), and angle-specific impulse were evaluated at each time point.


There were substantial differences in the number of contractions (ECC: 100.8 ± 54; EQI: 3.85 ± 1.1) and peak torque (mean: ECC: 215 ± 54 Nm; EQI: 179 ± 28.5 Nm). Both conditions elicited similar responses in 21/53 evaluated variables. EQIs resulted in greater vastus intermedius swelling (7.1–8.8%, ES = 0.20–0.29), whereas ECC resulted in greater soreness at the distal and middle vastus lateralis and distal rectus femoris (16.5–30.4%, ES = 0.32–0.54) and larger echogenicity increases at the distal rectus femoris and lateral vastus intermedius (11.9–15.1%, ES = 0.26––0.54). Furthermore, ECC led to larger reductions in concentric (8.3–19.7%, ES = 0.45–0.62) and isometric (6.3–32.3%, ES = 0.18–0.70) torque and RTD at medium-long muscle lengths.


A single session of EQIs resulted in less soreness and smaller reductions in peak torque and RTD versus impulse-equated ECC contractions, yet morphological shifts were largely similar. Long-term morphological, architectural, and neuromuscular adaptations to EQI training requires investigation.

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Delayed onset muscle soreness


Muscle thickness


Echo intensity


Fascicle length


Range of motion


Maximal voluntary isometric torque


Eccentric quasi-isometric








Coefficient of variation


Pennation angle


Rate of torque development


Compatibility interval


Effect size


  • Alemany JA, Delgado-Díaz DC, Mathews H, David JM, Kostek MC (2014) Comparison of acute responses to isotonic or isokinetic eccentric muscle action: differential outcomes in skeletal muscle damage and implications for rehabilitation. Int J Sports Med 35:1–7

    CAS  PubMed  Google Scholar 

  • Ando R, Taniguchi K, Saito A, Fujimiya M, Katayose M, Akima H (2014) Validity of fascicle length estimation in the vastus lateralis and vastus intermedius using ultrasonography. J Electromyogr Kinesiol 24:214–220

    PubMed  Google Scholar 

  • Ando R, Nosaka K, Tomita A, Watanabe K, Blazevich AJ (2017) Vastus intermedius vs vastus lateralis fascicle behaviors during maximal concentric and eccentric contractions. Scand J Med Sci Sports 28:1018–1026

    PubMed  Google Scholar 

  • Balog EM (2010) Excitation-contraction coupling and minor triadic proteins in low-frequency fatigue. Exerc Sport Sci Rev 38:135–142

    PubMed  PubMed Central  Google Scholar 

  • Bjørnsen T et al (2019) Type 1 muscle fiber hypertrophy after blood flow-restricted training in powerlifters. Med Sci Sports Exerc 51:288–298

    PubMed  Google Scholar 

  • Baker SJ, Kelly NM, Eston RG (1997) Pressure pain tolerance at different sites on the quadriceps femoris prior to and following eccentric exercise. Euro J Pain 1:229–233

    CAS  Google Scholar 

  • Caresio C, Molinari F, Emanuel G, Minetto MA (2015) Muscle echo intensity: reliability and conditioning factors. Clin Physiol Funct Imaging 35:393–403

    PubMed  Google Scholar 

  • Chapman D, Newton M, Sacco P, Nosaka K (2006) Greater muscle damage induced by fast versus slow velocity eccentric exercise. Int J Sports Med 27:591–598

    CAS  PubMed  Google Scholar 

  • Chen HL, Nosaka K, Chen TC (2012) Muscle damage protection by low-intensity eccentric contractions remains for 2 weeks, but not 3 weeks. Eur J Appl Physiol 112:555–565

    PubMed  Google Scholar 

  • Chen TC, Lin MJ, Chen HL, Lai JH, Yu HI, Nosaka K (2018) Muscle damage protective effect by two maximal isometric contractions on maximal eccentric exercise of the elbow flexors of the contralateral arm. Scand J Med Sci Sports 28:1354–1360

    CAS  PubMed  Google Scholar 

  • Citterio G, Agostoni E (1984) Selective activation of quadriceps muscle fibers according to bicycling rate. J Appl Physiol Respir Environ Exerc Physiol 57:371–379

    CAS  PubMed  Google Scholar 

  • de Ruiter CJ, Goudsmit JF, Van Tricht JA, de Haan A (2007) The isometric torque at which knee-extensor muscle reoxygenation stops. Med Sci Sports Exerc 39:443–453

    PubMed  Google Scholar 

  • Doguet V, Nosaka K, Plautard M, Gross R, Guilhem G, Guevel A, Jubeau M (2016) Neuromuscular changes and damage after isoload versus isokinetic eccentric exercise. Med Sci Sports Exerc 48:2526–2535

    CAS  PubMed  Google Scholar 

  • Douglas J, Pearson S, Ross A, McGuigan M (2017) Eccentric exercise: physiological characteristics and acute responses. Sports Med 47:663–675

    PubMed  Google Scholar 

  • Duchateau J, Enoka RM (2016) Neural control of lengthening contractions. J Exp Biol 219:197–204

    PubMed  Google Scholar 

  • Franchi MV, Reeves ND, Narici MV (2017) Skeletal muscle remodeling in response to eccentric vs. concentric loading: morphological, molecular, and metabolic adaptations. Front Physiol 8:1–16

    Google Scholar 

  • Franchi MV, Raiteri BJ, Longo S, Sinha S, Narici MV, Csapo R (2018a) Muscle architecture assessment: strengths, shortcomings and new frontiers of in vivo techniques. Ultrasound Med Biol 44:2492–2504

    PubMed  Google Scholar 

  • Franchi MV et al (2018b) Regional regulation of focal adhesion kinase after concentric and eccentric loading is related to remodelling of human skeletal muscle. Acta Physiol 223:e13056

    CAS  Google Scholar 

  • Frey Law LA, Evans S, Knudtson J, Nus S, Scholl K, Sluka KA (2008) Massage reduces pain perception and hyperalgesia in experimental muscle pain: a randomized, controlled trial. J Pain 9:714–721

    PubMed  Google Scholar 

  • Fulford J, Eston RG, Rowlands AV, Davies RC (2015) Assessment of magnetic resonance techniques to measure muscle damage 24 h after eccentric exercise. Scand J Med Sci Sports 25:28–39

    Google Scholar 

  • Gillies AR, Lieber RL (2011) Structure and function of the skeletal muscle extracellular matrix. Muscle Nerve 44:311–318

    Google Scholar 

  • Hopkins WG, Marshall SW, Batterham AM, Hanin J (2009) Progressive statistics for studies in sports medicine and exercise science. Med Sci Sports Exerc 41:3–9

    Google Scholar 

  • Hunter SK, Ryan DL, Ortega JD, Enoka RM (2002) Task differences with the same load torque alter the endurance time of submaximal fatiguing contractions in humans. J Neurophysiol 88:3087–3096

    PubMed  Google Scholar 

  • Hyldahl RD, Nelson B, Xin L, Welling T, Groscot L, Hubal MJ, Parcell AC (2015) Extracellular matrix remodeling and its contribution to protective adaptation following lengthening contractions in human muscle. FASEB J 29:2894–2904

    CAS  PubMed  Google Scholar 

  • Kjaer M (2004) Role of extracellular matrix in adaptation of tendon and skeletal muscle to mechanical loading. Physiol Rev 84:649–698

    CAS  PubMed  Google Scholar 

  • Lindstedt SL, LaStayo PC, Reich TE (2001) When active muscles lengthen: properties and consequences of eccentric contractions. News Physiol Sci 16:256–261

    CAS  PubMed  Google Scholar 

  • MacInnis MJ, McGlory C, Gibala MJ, Phillips SM (2017) Investigating human skeletal muscle physiology with unilateral exercise models: when one limb is more powerful than two. Appl Physiol Nutr Metab 42:563–570

    PubMed  Google Scholar 

  • Maffiuletti NA, Aagaard P, Blazevich AJ, Folland J, Tillin N, Duchateau J (2016) Rate of force development: physiological and methodological considerations. Eur J Appl Physiol 116:1091–1116

    PubMed  PubMed Central  Google Scholar 

  • Mangine GT et al (2018) Resistance training does not induce uniform adaptations to quadriceps. PLoS One 13:e0198304

    PubMed  PubMed Central  Google Scholar 

  • Noorkoiv M, Stavnsbo P, Aagaard P, Blazevich A (2010) In vivo assessment of muscle fascicle length by extended field-of-view ultrasonography. J Appl Physiol 109:1974–1979

    CAS  PubMed  Google Scholar 

  • Noorkoiv M, Nosaka K, Blazevich AJ (2014) Neuromuscular adaptations associated with knee joint angle-specific force change. Med Sci Sports Exerc 46:1525–1537

    PubMed  Google Scholar 

  • Oranchuk DJ, Nelson AR, Storey AG, Cronin JB (2019a) Scientific basis of eccentric quasi-isometric resistance training: a narrative review. J Strength Cond Res 33:2846–2859

    PubMed  Google Scholar 

  • Oranchuk DJ, Storey AG, Nelson AR, Cronin JB (2019b) Isometric training and long-term adaptations; effects of muscle length, intensity and intent: a systematic review. Scand J Med Sci Sports 29:484–503

    PubMed  Google Scholar 

  • Oranchuk DJ, Storey AG, Nelson AR, Neville JG, Cronin JB (2019c) Variability of multiangle isometric force-time characteristics in trained men. J Strength Cond Res (ahead of print)

  • Oranchuk DJ, Nelson AR, Storey AG, Cronin JB (2020b) Variability of regional quadriceps architecture in trained men assessed by B-mode and extended-field-of-view ultrasonography. Int J Sports Physiol Perform 15:430–436

    Google Scholar 

  • Oranchuk DJ, Neville JG, Nelson AR, Storey AG, Cronin JB (2020c) Variability of concentric angle-specific isokinetic torque and impulse assessments of the knee extensors. Physiol Meas 41:01NT02

    PubMed  Google Scholar 

  • Oranchuk DJ, Stock MS, Nelson AR, Storey AG, Cronin JB (2020d) Variability of regional quadriceps echo intensity in active young men with and without subcutaneous fat correction. Appl Physiol Nutr Metab 45:745–752

    CAS  PubMed  Google Scholar 

  • Pamboris GM, Noorkoiv M, Baltzopoulos V, Mohagheghi A (2019) Dynamic stretching is not detrimental to neuromechanical and sensorimotor performance of ankle plantarflexors. Scand J Med Sci Sports 29:200–212

    PubMed  Google Scholar 

  • Peñailillo L, Blazevich A, Numazawa H, Nosaka K (2013) Metabolic and muscle damage profiles of concentric versus repeated eccentric cycling. Med Sci Sports Exerc 45:1773–1781

    PubMed  Google Scholar 

  • Peñailillo L, Blazevich A, Numazawa H, Nosaka K (2015) Rate of force development as a measure of muscle damage. Scand J Med Sci Sports 25:417–427

    PubMed  Google Scholar 

  • Philippou A, Maridaki M, Bogdanis GC, Halapas A, Koutsilieris M (2009) Changes in the mechanical properties of human quadriceps muscle after eccentric exercise. Vivo 23:859–865

    CAS  Google Scholar 

  • Radaelli R, Bottaro M, Wilhelm EN, Wagner DR, Pinto RS (2012) Time course of strength and echo intensity recovery after resistance exercise in women. J Strength Cond Res 26:2577–2584

    PubMed  Google Scholar 

  • Rudroff T, Barry BK, Stone AL, Barry CJ, Enoka RM (2007) Accessory muscle activity contributes to the variation in time to task failure for different arm postures and loads. J Appl Physiol 102:1000–1006

    PubMed  Google Scholar 

  • Schaefer LV, Bittmann FN (2017) Are there two forms of isometric muscle action? Results of the experimental study support a distinction between a holding and a pushing isometric muscle function BMC Sports Sci Med Rehabil 9:1–13

    Google Scholar 

  • Schmitz RJ, Westwood KC (2001) Knee extensor electromyographic activity-to-work ratio is greater with isotonic than isokinetic contractions. J Athl Train 36:384–387

    PubMed  PubMed Central  Google Scholar 

  • Sharifnezhad A, Marzilger R, Arampatzis A (2014) Effects of load magnitude, muscle length and velocity during eccentric chronic loading on the longitudinal growth of the vastus lateralis muscle. J Exp Biol 217:2726–2733

    PubMed  Google Scholar 

  • Smith TO, Bowyer D, Dixon J, Stephenson R, Chester R, Donell ST (2009) Can vastus medialis oblique be preferentially activated? A systematic review of electromyographic studies. Physiother Theory Pract 25:69–98

    PubMed  Google Scholar 

  • Spurway NC (2007) Hiking physiology and the “quasi-isometric” concept. J Sports Sci 25:1081–1093

    PubMed  Google Scholar 

  • Stock MS, Oranchuk DJ, Burton AM, Phan DC (2020) Age, sex, and region-specific differences in skeletal muscle size and quality. Appl Physiol Nutr Metab (ahead of print)

  • Tabuchi A et al (2019) Regional differences in Ca2+ entry along the proximal-middle-distal muscle axis during eccentric contractions in rat skeletal muscle. J Appl Physiol 127:828–837

    CAS  PubMed  Google Scholar 

  • Tetsuya H et al (2020) Relationship between muscle swelling and hypertrophy induced by resistance training. J Strength Cond Res (ahead of print)

  • Ullrich B, Kleinöder H, Brüggemann G-P (2010) Influence of length-restricted strength training on athlete’s power-load curves of knee extensors and flexors. J Strength Cond Res 24:668–678

    PubMed  Google Scholar 

  • Valamatos MJ, Tavares F, M SR, Veloso AP, Mil-Homens P (2018) Influence of full range of motion vs equalized partial range of motion training on muscle architecture and mechanical properties. Eur J Appl Physiol 118:1969–1983

    PubMed  Google Scholar 

  • Varanoske AN, Fukuda DH, Boone CH, Beyer KS, Stout JR, Hoffman JR (2017a) Homogeneity of echo intensity values in transverse ultrasound images. Muscle Nerve 56:93–98

    PubMed  Google Scholar 

  • Varanoske AN, Fukuda DH, Boone CH, Beyer KS, Stout JR, Hoffman JR (2017b) Scanning plane comparison of ultrasound-derived morphological characteristics of the vastus lateralis. Clin Anat 30:533–542

    PubMed  Google Scholar 

  • Verkhoshansky Y, Siff MC (2009) Supertraining, 6th edn. Ultimate Athlete Concepts, Rome

    Google Scholar 

  • Watanabe K, Kouzaki M, Moritani T (2014) Non-uniform surface electromyographic responses to change in joint angle within rectus femoris muscle. Muscle Nerve 50:794–802

    PubMed  Google Scholar 

  • Yeung SS, Yeung EW (2008) Shift of peak torque angle after eccentric exercise. Int J Sports Med 29:251–256

    CAS  PubMed  Google Scholar 

  • Young HJ, Jenkins NT, Zhao Q, Mccully KK (2015) Measurement of intramuscular fat by muscle echo intensity. Muscle Nerve 52:963–971

    PubMed  PubMed Central  Google Scholar 

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Dustin J. Oranchuk was supported by the Auckland University of Technology’s Vice-Chancellors Doctoral Scholarship.

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DJO, ARN, AGS, and JBC formulated the research question and experimental design. DJO performed the experiments. DJO and SND analyzed data and created figures. DJO performed the statistical analysis, formulated the tables, and wrote the manuscript. DJO, ARN, AGS, and JBC reviewed and revised the manuscript. All authors approved the final version.

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Correspondence to Dustin J. Oranchuk.

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Communicated by Olivier Seynnes.

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Oranchuk, D.J., Nelson, A.R., Storey, A.G. et al. Short-term neuromuscular, morphological, and architectural responses to eccentric quasi-isometric muscle actions. Eur J Appl Physiol 121, 141–158 (2021).

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  • Acute
  • Angle-specific
  • Echo intensity
  • Force
  • Length-tension
  • Physiology
  • Rehabilitation
  • Resistance exercise
  • Torque
  • Ultrasound